Definition
A radar receiver circuit that automatically reduces the receiver's sensitivity for echoes returning from nearby targets and progressively increases sensitivity for echoes returning from more distant targets. This compensates for the fact that close targets produce strong return signals while distant targets produce weak ones, allowing the radar display to show all targets at roughly comparable brightness regardless of range.
Plain English
A radar feature that turns the receiver down for nearby echoes and turns it up for far-away echoes, so close targets don't wash out the screen and far targets still show up clearly.
Context Anchor
Seen in airborne weather radar, ground radar, and radar maintenance discussions.
Derivation
Sensitivity refers to how strongly the receiver responds to incoming signals. Time refers to the time delay between the radar pulse going out and the echo coming back, which corresponds to target distance. Control means the circuit automatically varies the sensitivity based on that elapsed time. So the name literally describes what it does: it controls sensitivity based on time.
Why Pilots Care
Prevents nearby ground or weather returns from overwhelming the display and hiding important distant targets.
Grounding Statement
Right after the radar sends a pulse, it turns down its listening strength for close echoes, then turns it back up as it waits for echoes from farther away.
Intuition Check
Sensitivity Time Control is not about how quickly a pilot reacts. Here, sensitivity means how strongly the radar receiver listens, and time is used because echo return time tells the radar how far away the target is.
Example Sentence 1
The weather radar's sensitivity time control kept nearby rain showers from overpowering the display so the crew could still see the larger cell building 60 miles ahead.
Example Sentence 2
During radar checkout the technician confirmed the sensitivity time control was varying gain correctly with range.